Claugher, D., (editor), 1990

Reviewed by David M. Jarzen*, Canadian Museum of Nature, Ottawa, Ontario,
in CAP Newsletter 16(1):8-9, 1993.

Over the years the Systematics Association has published a series of high quality "textbook" style volumes covering nearly all aspects of systematics and taxonomy. Volume 41, skillfully edited by Claugher, carries on this tradition. Although the book was published in 1990, I feel it is important to bring this contribution to the attention of CAP Newsletter readers, since several papers comprising this volume are of potential interest to palynologists.

The purpose or aim of the volume was to update an early Systematics Association volume, produced in 1971, entitled Scanning Electron Microscopy: Systematic and Evolutionary Applications (Heywood 1971). Since 1971, the use of SEM in taxonomic investigations and improvements to the machines and preparation techniques warrant the publication of this book. Rowley et al. (1987-1988) have graphically illustrated the increased use in SEM investigations in the description of pollen grains. Their figures indicate as much as a 46% use of SEM in papers published in 1982-1983. Certainly taxonomic studies and systematic approaches to palynology are enhanced using SEM and TEM applications, which are indeed considered necessary tools by many investigators.

The 13 chapters of Volume 41 are devoted to applications using improved or new SEM capabilities which include lower field emission, viewing of uncoated materials, viewing of frozen materials and digitization of the analogue signal. Blackmore and Barnes (Chapter 1) review the study of pollen development using the SEM from examples of Lactuceae (Compositae) pollen ontogeny, while Hennipman (Chapter 2) relates the significance of SEM for character analysis of both exospore and perispore in the Polypodiaceae. The third and last chapter devoted to pollen or spores is by Harley and Ferguson on the role of SEM in pollen morphology and plant systematics, in which the authors provide specific attention to palynomorph preparation and terminology used in describing exine features observed with SEM.

Other chapters concentrate on studies of the epidermal surface in plants (Barthlott), plant cuticle (Hill and Dilcher), taxonomy of living planktonic thecate dinoflagellates (Lewis and Dodge), marine ascomycetes (Moss), diatoms (Paddock and Sims), paleobotanical macrofossils (Hill), testate amoebae (Ogden), bryozoans (Taylor), helminths (Gibbons and Khalil), and digitization in SEM (Wagener).

The contribution by Hill (Chapter 9) discusses the many and varied applications of SEM to paleobotany, including the study of fusainized material, impressions and opaque mineralizations in limonite and pyrite. I found the section on replica palynology especially interesting. As we are all aware, palynomorphs are preserved as compressions with complementary impressions often preserved within rock matrix. However, some rock types, i.e., most red bed matrices and those from surface outcrops in tropical and hot arid regions, do not yield palynomorphs for a variety of reasons, oxidation being perhaps the major culprit. These "barren" samples, however, may in fact contain well-preserved impressions of the palynomorphs once contained within the rock matrix. Using relatively elaborate techniques, Hill was able to produce beautifully detailed replicas of the impressions of Permian fern spores from Saudi Arabia. Although success using the technique described by Hill depends upon several factors, including palynomorph density and sufficiently detailed imprints, it may prove to be another method to provide the palynologist with at least some data as to the nature of the "once contained" palynoflora. The chapter is worthy of our attention.

The book appears very well edited, with generally clear and well reproduced photographic plates. The book may serve as a reference-type text for palynologists who use SEM routinely as a tool in their research program.

References

Heywood, V. H., editor, 1971. Scanning Electron Microscopy: Systematic and Evolutionary Applications. Systematics Association Special Volume 4, Academic Press, London and New York.

Rowley, J. R., J. J. Skvarla, and E. L. Vezey, 1987-1988. Evaluating the relative contributions of SEM, TEM and LM to the description of pollen grains. Journal of Palynology, G. Thanikaimoni Memorial Volume, Vol. 23-24, pp. 27-28.
 

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*Present address: Florida Museum of Natural History, Department of Natural Sciences, University of Florida, P.O.Box 117800, Gainesville, Florida 32611-7800, U.S.A.